Tail gate latch assembly



Feb. 21, 1967 w. s. APPLEMAN TAIL GATE LATCH ASSEMBLY 4 SheetsSheet 1 Filed June 19, 1964 Hu I ll FIG.

INVENTOR. WILLIAM S. APPLEMAN ATTORNEYS W. S- APPLEMAN TAIL GATE LATCH ASSEMBLY Filed June 19, 1964 4 Sheets-Sheet 2 |||I|u u. "Hummu- Q I! l W HUI." 44 a 5O ll nnw 42 g I I uuln f 7 g I M) Wm); s O i. l 0 20 58 Q 7a .3

FIG. 2

INVENTOR.

WILLIAM S. APPLEMAN Feb. 21, 1967 w. s. APPLEMAN 3,305,263

TAIL GATE LATCH ASSEMBLY Filed June 19, 1964 4 Sheets-Sheet 5 FIG. 3

INVENTOR. WILLIAM S. APPLEMAN BY Z22 ATTORNEYS Feb. 21, 1967 v w. s. APPLEMAN 3,305,263

TAIL GATE LATCH ASSEMBLY Filed June 19, 1964 4 Sheets-Sheet 4 FIG. 4

INVENTOR. WILLIAM S. APPLEMAN law "ATTORNEYS United States Patent 3,305,26 TAH. GATE LATCH ASSEMBLY William S. Appleman, Galion, Ohio, assignor, by mesne assignments, to Harsco Corporation, Harrisburg, Pa. Filed June 19, 1964, Ser. No. 376,384 2 Claims. (Cl. 29656) The present invention relates generally to truck bodies or the like and specifically to an improved tailgate latch mechanism for use with top-hinged tailgates.

In general, the tailgate latch mechanism of the present invention comprises, in combination, a plurality of slideable bottom hooks each connected by a first linkage means to a common rock shaft actuating the bottom hooks to engage the lower margin of a tailgate, a latch means disposed to engage the outer upper margin of the tailgate, second linkage means connecting said latch means to said rock shaft, guide means for said bottom hooks and actuator means for rotating said rock shaft.

In accordance with the present invention, the novel construction of the release mechanism permits a plurality of bottom hooks to be actuated simultaenously at various points across the lower margin of a top-hinged tailgate of a truck body for opening or securely closing the tailgate.

As another aspect of the present invention, the novel construction of the release mechanism permits safe and convenient actuation of all the bottom hooks by a single manually operated handle placed at a remote location.

As another aspect of the present invention, the novel slideably mounted bottom hooks are adapted to make closing engagement with the tailgate when the tailgate is partially open and hence at a greater distance from the dump body than was possible with prior release mechanisms.

As another aspect of the present invention, the simple and durable construction of the release mechanism permits long service with a minimum of maintenance.

As a further aspect of the present invention, the novel construction of the release mechanism permits manufacture and fabrication of the component parts at relatively low cost.

It is therefore an object of the present invention to provide a novel tailgate latch mechanism having a plurality of bottom hooks actuated simultaneously to engage or disengage the tailgate.

It is another object of the present invention to provide a tailgate latch mechanism that actuates all the bottom hooks by means of a single handle manually operated from a safe and convenient location.

It is another object of the present invention to provide a tailgate latch mechanism capable of engaging the lower margin of the tailgate at a more open position as compared to prior mecahnisms thereby eliminating the need of manual assistance in pushing the tailgate closed.

It is another object of the present invention to provide a tailgate latch mechanism adapted to simultaneously actuate both bottom engaging and side engaging latch elements.

It is another object of the present invention to provide a tailgate latch mechanism that provides long service with a minimum of maintenance.

It is a further object of the present invention to provide a tailgate latch mechanism which may be manufactured and fabricated at relatively low cost.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings wherein a preferred form of embodiment of the invention is clearly shown.

3,305,263 Patented Feb. 21, 1967 In the drawings:

FIG. 1 is a side view of the tailgate latch mechanism of the present invention with said mechanism disposed in a closed position being mounted on the rear portion of 'a truck body having a top-hinged tailgate;

FIG. 2 is a side view of the tailgate latch mechanism shown in FIG. 1 with said mechanism disposed in an open position;

FIG. 3 is a top view of the tailgate latch mechanism shown in FIG. 1 'as seen when removed from the dump body; and

FIG. 4 is an isolated enlarged perspective view of a linkage comprising a portion of the mechanism of the preceding figures.

Referring in detail to the drawings, a side view of the tailgate latch mechanism of the present invention is illustrated in FIG. 1.

A plurality of slideably mounted bottom hooks 20 are positioned to clamp the lower edge portion of tailgate 22 along angle 24 at transversely spaced intervals. Bottom hooks 20 are provided with inclined cam surfaces 73 and 75.

A common rock shaft 26, extending transversely relative to the truck body, indicated generally at 28, is rotatably mounted by bearing blocks 27 afiixed to the truck body. Rock shaft 26 is connected to each bottom hook 20 by a respective first linkage means, indicated generally at 30. Each first linkage means 30 includes an arm 32 mounted on rock shaft 26 and a respective pair of link members 34 pivoted at one end to arm 32 and at the other end to the eye of an adjustable eye bolt 38 at a pin :0. Bolt 38 is screwed into a threaded bore in a respective bottom hook 20 and each bolt is provided with a. lock nut 39. To individually adjust the hook pressure exerted on the tailgate by each hook 20, pin 40 is removed to free eye bolt 38 for rotation to adjust its axial extension.

A latch means 42 disposed at each outer end of the upper portion of tailgate 22 to engage angle 44 is pivoted intermediate its ends to pivot pin 46 mounted to a bracket 45 attached to each side wall of truck body 28.

Referring to FIGS. 1, 2 and 4, a respective second linkage means, indicated generally at 51, connects each latch means 42 to rock shaft 26 and includes a respective connecting rod 48 pivoted to each latch means 42 by a respective pivot pin 50. Each rod 48 is provided with an int-urned lower end portion 52 connected to a respective first link member 54.

As is best seen in the perspective view of FIG. 4, each linkage means 51 further includes a bell crank 56 and a second link member 62. Each first link member 54 is .pivotally connected to one end of a respective bell crank 56 at a cross shaft 58 which is supported by a respective pair of brackets 60 affixed to truck body 28. Each bell crank 56 is pivoted at the other end to said respective second link member 62 at pivot pin 64 and each second link member 62 is in turn pivoted to an arm 65 at a pivot pin 77, said arm 65 being fastened to rock shaft 26. Thusly, all latch means 42 operate simultaneously and with bottom hooks 20 with rotation of rock shaft 26.

A plurality of hook guides 66 fastened to the underside of truck body 28 include follower portions 67 and 69 and a guide flange 72 which guides bottom hooks 20 through hook guide 66 and slot provided in body frame member 71.

With continued reference to FIG. 1, a stop means 11 is rigidly atached to truck body 28 in overlying relationship with the shank portion of hook 20, such stop means cooperates with follower portion 69 in absorbing rotational loads applied to said hooks by said tailgate.

In operation, as bottom hooks 20 slide rearwardly through hook guides 66, upper cam surfaces 73 engage the respective upper follower portions 67 and thereby shift the path of bottom hooks vertically downwardly with respect to the lower edge portion of tailgate 22.

In operation, handle 74 is manually pivoted counterclockwise, as viewed in FIG. 1, thereby turning shaft 26 to shift bottom hooks 20 via first linkage means 30 to slide them through slots 70 and hook guides 66 to open position illustrated in FIG. 2. With bottom hooks 20 in an open position, the lower margin of tailgate 22 is released.

Simultaneously the same counter-clockwise rotation impar-ted to shaft 26 actuates latch means 42 to pivot it to an open position about pivot pin 46 as connecting rod 48 is moved downwardly through the operation of second linkage means 51, as illustrated in FIG. 2. With both latch means 42 and bottom hooks 20 in an open position, tailgate 22 is free to swing about its top hinges.

'I o securely lock the tailgate 22 in a closed position, the handle 74 is rotated clockwise actuating bottom books 20 and latch means 42 to return them to the closed position of FIG. 1. As hooks 20 are shifted to the left, lower cam surfaces 75 on the books engage lower follower 67 whereby the paths of the hooks are shifted upwardly.

In the closed position the axis defined by the center of pivot pins 36 and 40 has move-d above the center of 81 of rock shaft 26 thereby locking the linkage in the closed position of FIG. 1.

While the form of embodiment of the present invention as herein dis-closed constitutes a preferred: form, it is to be understood that other forms might be adopted, all coming within the scope of the claims which .follow.

I claim:

1. A release mechanism for a truck body having a tophin'ged tailgate comprising, in combination, a plurality of slideable bottom hooks positioned to clamp the lower edge portion of said tailgate at transversely spaced intervals, said bottom hooks including inclined upper and lower edges; first follower means on said truck body and engaging said inclined lower edges for shifting said hooks upwardly; second follower means on said truck body and engaging said inclined upper edges for shifting said hooks downwardly; stop means on said truck body and overlying the shanks of said hooks for absorbing rotational loads applied to said hooks by said tailgate; a transversely extending common rock shaft for actuating said bottom hooks; at least one latch means disposed to engage an outer end portion of the upper margin of said tailgate; guide means for said bottom hooks disposed adjacent the rear edge portion of said truck body; an arm including an inner end mounted on said rock shaft and an outer end; a first link including a first end pivotally connected to one of said bottom hooks and a second end pivotally connected to said outer end of said first arm, the central portion of said link being offset with respect to a line through the pivot centers of said link ends whereby said arm and link can be moved beyond center to lock said bottom hooks against said tailgate; a linkage including a pivoted lever connecting said latch means to said rock shaft; and an actuator for rotating said rock shaft to simultaneously actuate said hooks and said latch means.

2. A release mechanism for a truck body having a hinged tailgate comprising, in combination, a plurality of slideable bottom hooks positioned to clamp the lower edge portion of said tailgate at transversely spaced intervals, said bottom hooks including inclined upper and lower edges; first follower means on said truck body and engaging said incline-d lower edges for shifting said hooks upwardly; second follower means on said truck body and engaging said inclined upper edges for shifting said hooks downwardly; stop means on said truck body and overlying the shanks of said hooks for absorbing rotational loads applied to said hooks by said tail-gate; a transversely extending common rock shaft for actuating said bottom hooks; at least one latch means disposed to engage an outer end portion of the upper margin of said tailgate; guide means for said bottom hooks disposed adjacent the rear edge portion of said truck body; an arm including an inner end mounted on said rock shaft and an outer end; a first link including a first end pivotally connected to one of said bottom hooks and a second end pivotally connected to said outer end of said first arm, the central portion of said link being offset with respect to a line through the pivot centers of said link ends whereby said arm and link can be moved beyond center to lock said bottom hooks against said tailgate; a second arm including an inner end mounted on said rock shaft and an outer end; a pivotally mounted lever member; a second link connecting one end of said lever member with said outer end of said second arm; a third link connecting the other end of said lever member with said latch means; and an actuator for rotating said rock shaft to simultaneously actuate said hooks and said latch means.

References Cited by the Examiner UNITED STATES PATENTS 2,530,346 11/1950 Wolf 292--113 2,949,327 8/1960 Totaro et al. 29226 3,078,121 2/196-3 Dempster et a1 29656 MILTON BUCHLER, Primary Examiner.

BENJAMIN HERSH, Examiner.

J. H. BRANNEN, Assistant Examiner. 

1. A RELEASE MECHANISM FOR A TRUCK BODY HAVING A TOPHINGED TAILGATE COMPRISING, IN COMBINATION, A PLURALITY OF SLIDEABLE BOTTOM HOOKS POSITIONED TO CLAMP THE LOWER EDGE PORTION OF SAID TAILGATE AT TRANSVERSELY SPACED INTERVALS, SAID BOTTOM HOOKS INCLUDING INCLINED UPPER AND LOWER EDGES; FIRST FOLLOWER MEANS ON SAID TRUCK BODY AND ENGAGING SAID INCLINED LOWER EDGES FOR SHIFTING SAID HOOKS UPWARDLY; SECOND FOLLOWER MEANS ON SAID TRUCK BODY AND ENGAGING SAID INCLINED UPPER EDGES FOR SHIFTING SAID HOOKS DOWNWARDLY; STOP MEANS ON SAID TRUCK BODY AND OVERLYING THE SHANKS OF SAID HOOKS FOR ABSORBING ROTATIONAL LOADS APPLIED TO SAID HOOKS FOR ABSORBING ROTATIONAL LOADS TENDING COMMON ROCK SHAFT FOR ACTUATING SAID BOTTOM HOOKS; AT LEAST ONE LATCH MEANS DISPOSED TO ENGAGE AN OUTER END PORTION OF THE UPPER MARGIN OF SAID TAILGATE; GUIDE MEANS FOR SAID BOTTOM HOOKS DISPOSED ADJACENT THE REAR EDGE PORTION OF SAID TRUCK BODY; AN ARM INCLUDING AN INNER END MOUNTED ON SAID ROCK SHAFT AND AN OUTER END; A FIRST LINK INCLUDING A FIRST END PIVOTALLY CONNECTED TO ONE OF SAID BOTTOM HOOKS AND A SECOND END PIVOTALLY CONNECTED TO SAID OUTER END OF SAID FIRST ARM, THE CENTRAL PORTION OF SAID LINK BEING OFFSET WITH RESPECT TO A LINE THROUGH THE PIVOT CENTERS OF SAID LINK ENDS WHEREBY SAID 